How can I enforce that a link type is only used ONCE on a particular ticket.

[Celina Kincaid]

TicketA has 5 available link types.

TicketB has 5 available link types.

How do I lock down the project where Ticket A lives to restrict to only a single instance of the 'ZZZ' link type?  It can have any other link type multiple times.

Example:

• When viewing ticketA, you can link to ticketB with linktype of 'ZZZ' ONLY if no other linktype of 'ZZZ' exists on ticketA.
• When viewing ticketB, you can link back to ticketA with the linktype of 'ZZZ' ONLY if no other linktype of 'ZZZ' exists on ticketA

Basically, the restriction is on the project that holds ticketA so no matter where the link is coming from OR going to, ticketA will never have more than one link of linktype 'ZZZ'. 

Bonus kudos if someone knows how to do this and can lock it down based on projecttype. 

[Trudy Claspill]

Hello @Celina Kincaid 

That is not something that is available with Jira native functionality. It is not possible to restrict the type of link that can be selected to link issues.

You could potentially create Automation Rules that would

1. Trigger each time a new issue link was created using the ZZZ link type
2. Check if one of the issues in the link pair was from specified project
3. Check if that issue already has another linked issue using that link type
4. remove the new link and send an email to an appropriate person.